African and Tropical Western Pacific Deep Convective Impact to the Tropical Lower Stratosphere

In regions of very deep tropical convection, material transfer of water vapor, evaporating cloud ice, aerosols and low ozone between troposphere and stratosphere has important implications for the composition of the middle atmosphere, and feedbacks to temperature regulation at the earth’s surface. The two largest regions of influence in the deep tropics are Africa and the maritime continent in the Western Pacific. Satellite instruments on NASA’s A-Train satellite constellation provide observations of water vapor, ozone and the tops of deep convective clouds. This presentation features observations from the Microwave Limb Scanner (MLS), the Clouds and Aerosol Lidar with Orthogonal Polarization (CALIOP) and the Cloud Profiling Radar (CPR). A challenge is to match these observations spatially, so we re-average the CALIOP and (where available) CPR cloud and aerosol profiles to match the MLS observation kernel.

In this way we compare total water, and relationships between convection, ozone and aerosols in these two regions. We find that deep convection has the larger influence on cooling the tropical tropopause over the Western Pacific, while there is more cloud ice near the tropopause layer over Africa. We correlate these two observations with near-tropopause and lower stratospheric aerosols and ozone. Using eleven years of data that span several ENSO cycles, we also examine the relationship between high altitude cloud ice, temperature and ENSO phase in these two regions.